1. Field of the Invention
The present invention generally relates to an automobile rear body structure, and more particularly, to an automobile rear openable structure such as a back door which covers a rear portion of an automobile vehicle and can be opened with respect thereto.
2. Description of the Prior Art
Conventionally, there have been proposed various kinds of automobile rear openable structures. Some of them are of a type in which only a trunk lid can be opened with respect to a rear portion of an automobile vehicle. Some of the others are of a type in which both of the trunk lid and a rear windshield glass can be opened with respect to the rear portion of the automobile vehicle.
The Japanese Utility Model Laid-Open Application No. 62-79616 discloses a back door of an automobile vehicle which can be opened in two steps. A luggage door alone or together with a rear windshield glass can be opened as occasion demands. The luggage door is hingedly connected at its upper end with a lower end of the rear windshield glass, which is further hingedly connected at its upper end with a rear header. The luggage door corresponds to the trunk lid.
Such a structure can provide a relatively wide opening when the back door is opened. However, this kind of structure is disadvantageous in that various members tend to be collected on the rear header in order to raise the rigidity thereof. The reason for this is that the rear header acts as a fulcrum of the back door when opened. Accordingly, the distance between the rear header and a person occupying a rear seat i.e., the head clearance is disadvantageously reduced.
Furthermore, since the back door becomes long and heavy, an auxiliary means, for example, a damper stay or the like required for opening the back door inevitably becomes large-sized, resulting in an increased cost. Besides, the rear windshield glass is thickened to be raised in rigidity, resulting undesirably in its increased weight and cost.
On the other hand, conventional automobile vehicles of the sedan style in which only the trunk lid can be opened have an ample head clearance. However, the automobile vehicles of this kind are disadvantageous in that the trunk lid can not ensure a sufficient opening for loading and unloading luggages.